Smoking is a major, persistent health hazard because of its potent reward properties, but no research has systematically explored these properties. We propose to develop an apparatus to both ration and measure cigarette smoking on a puff-by-puff basis. Volunteer adult smokers will then have smoking made available to them according to schedules of reinforcement which are familiar for other rewards, and their operant behavior will be compared with that for other rewards. Schedules that vary the delay of reward from the moment of choice seem especially important both for understanding an addictive behavior like smoking and for making sense of human motivational conflict in general. It has hitherto been impossible to study delay of reward in adults for want of a practical primary reward, but such a study should be possible with the proposed methodology for smoking.